A driver-side airbag device arranged in a steering wheel comprises a retainer, an airbag having a gas inlet of which periphery is attached to the retainer, a cover for covering the airbag in the folded state, and an inflator for generating gas. As the inflator is actuated to generate gas, the airbag is inflated, the cover is torn, and the airbag is largely deployed into a vehicle cabin.
As an example of the driver-side airbag device, there is an airbag device in which a horn switch is turned on by pressing the cover of the airbag so as to blare a horn. Such airbag devices are categorized into a type in which the airbag device is entirely moved in the direction of pressing and a type in which only the cover is moved in the direction of pressing.
As an example of the airbag device of the type in which the airbag device is entirely moved, there is an airbag device comprising an airbag unit. The airbag unit includes a retainer, an inflator which is fixed to the retainer to generate gas, a folded airbag, and a cover which is disposed to cover the folded airbag and is moved when the cover is pressed. The airbag device further comprises a supporting plate (supporting body) which is fixed to a steering wheel, a biasing means which is disposed between the airbag unit and the supporting plate to bias said airbag unit, and a horn switch which is disposed at substantially the same position as the biasing means between the airbag unit and the supporting plate (see Patent document 1, for example).    Patent document 1: Japanese Patent No. 3439336